The participle is marching.
Marching
Marching
"The ancient people crossed the land bridge, Beringia, following herds of animals."
Slowly
The verb in the sentence 'he crossed the bridge' is crossed. The word 'crossed' comes from the verb 'to cross'.
The word 'crossed' in a verb and an adjective.The word crossed is the past participle, past tense of the verb to cross (crosses, crossing, crossed). The past participle of the verb is also an adjective (crossed fingers or crossedbridges).The word cross is is a noun, a verb, or an adjective.The noun cross is a singular, common noun; a word for a mark, object, or figure formed by two short intersecting lines or pieces, a word for a thing.
We crossed the street briskly.
The sentence should be: You crossed the Cambodian border. In that instance, Cambodian would be the adjective, as it is describing the noun which is border.
Have you ever crossed the frontier.
a look of anguish crossed Ben face.
When I was in the plane I crossed a Land Plain
Of course I would have crossed the mine field more quickly if I had crossed it less carefully!